Terminals Of Ecu [02/2014 - ]

HINT: 

Perform the inspection from the harness side with the connectors connected.

Fig 1: Steering Wheel Heater Controller Assembly Connector End Views

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1. Measure the voltage or resistance according to the value(s) in the table below.

   Terminal No. (Symbol)	Terminal Description	Condition	Specified Condition
   A-1 (CCU) - Body ground	LED output signal	Power switch on (IG), Steering heater switch on	Below 3 V
   A-2 (CCV) - Body ground	Steering heater switch input signal	Power switch on (IG), Steering heater switch on	11 to 14 V
   A-3 (CCX) - Body ground	Ground	Always	Below 1 Ω
   A-4 (CCW) - Body ground	IG power supply	Power switch on (IG)	11 to 14 V
   B-1 (TH1) - Body ground	Thermistor input signal	Power switch on (IG), Steering heater switch on at 0 to 40°C (32 to 104°F)	1.5 to 4.5 V*1
   B-2 (TH2) - Body ground	Thermistor ground	Power switch on (IG), Steering heater switch on	Below 1 V
   B-3 (SH2) - Body ground	Heater output signal	Power switch on (IG), Steering heater switch on	11 to 14 V*2
   B-4 (SH1) - Body ground	Heater ground	Power switch on (IG), Steering heater switch on	Below 1 V

   HINT: 

   • *1: When ambient temperature is 0 to 40°C (32 to 104°F).
   • *2: The current to the heater turns ON/OFF depending on the temperature of the thermistor. As a result, it may take several minutes before a voltage value is output.